在鑄件廢品当中,很多是由于产生了縮孔和縮松造成的。縮孔和縮松是怎样产生的呢?一般說来是因为鑄件澆鑄后,液体金屬在凝固过程中,体积要縮小,如果得不到足够液体金屬来补充,就会在鑄件最后冷却的地方产生縮孔和縮松。图1就是鑄件逐漸凝固产生縮孔的示意图。使用冷铁是防止鑄件产生縮孔和縮松的一种有效办法。冷铁可以分內冷铁和外冷铁两种:內冷铁是放在型腔里面鑄件最容易产生縮孔的地方,一般 Among the cast scrap, many are due to shrinkage and shrinkage. Shrinkage and shrinkage is how it is produced? Generally speaking, because the casting casting, the liquid metal in the solidification process, the volume should be reduced, if not enough liquid metal to make up, it will be in the final cooling of the casting produced Shrinkage and shrinkage. Figure 1 is a schematic view of the casting solidification shrinkage. The use of cold iron is to prevent the casting shrinkage and shrinkage of an effective way. Cold iron can be divided into two types of cold iron and cold iron: Internal cooling iron is placed in the cavity where the most likely to produce shrinkage cramps, general